Multiple expansion engine



BURNHAM 2,010,845

EXPANSION ENGINE 19,54 7 Sheets-Sheet l MULTIPLE Filed Jan. 27,

Aug. 13, 1935.

H. s. BURNHAM 2,010,845

MULTPLE EXPANSION ENGINE Filed Jan. 27, 1934 7 Sheets-Sheet 2 Aug. 13, 1935.

. Q ww ww mw mv 5m. uw, w n mw Allg 13, 1935. H. s.` BUrNHAM MULTIPLE EXPANSION ENGINE Filed Jan. 2'7, 1934 7 Sheets-Sheet 5 NVENTOR Harry Burn/1am BY/ g v 'A l EYf Aug. 13, 1935. H. s. BURNHAM MULTIPLE EXPANSION ENGINE '7 sheets-sheet 4 Filed Jan. 27, 1934 m a fm r1 um. R m5. m7 wm H BY ATI NEY ug- 13, 1935 H. s. BURNHAM MULTIPLE EXPANSION ENGINE Filed Jan. 27, 1954 7sheets-sheet 5 INVENTOR Har/'17 5` Burn/1am A NEY Aug. 13, 1935. H. s. BURNHAM 2,010,845

MULTIPLE EXPANS ION ENGINE lMT RNEY '7 Sheets-Sheet 7 smul H. s.' BURNHAM Filed Jan. 27, 1934 MULTIPLE EXPANSION ENGINE mmf! Aug. 13, 1935.

lfBurn/mm A ORNEY Patented Aug. 13, 1935 UNITED ASTATES PATENT OFFICE i rIhis Vinvention relates to multiple expansion engines and particularly to apparatus for distributing steam to the cylinders of such an engine, wherebythe operation of the engine is controlled to eifect, at certain times, single' expansion operation of all of the cylinders, or to effect, at other timespmultiple expansion operation.

i' An object of the invention is to'provide apparatusfor distributing steamof the characteraforementioned. whereby a triple expansion engine will start with live steamin all -of its cylinders, i. e. in single expansion operation, and will be so driven for a few strokes and will normally thereupon automatically go into triple expansion operation, whereby'the engine may bemanually controlled for keeping said engine in single ex-4 i pansion operation of the engine including inter# cepting valve means for controlling the flow of live steam and exhaust steam from the higher i pressure cylinder or cylinders tothe low pressure cylinder or cylinders which includes a high pressure steam reducing valve arranged in proximity to the low pressurel cylinder or cylinders so as to permit a relatively short travel of the reduced live steam to the low pressure cylinder or cylinders, thereby eliminating the previous practice ci passing the live steam first to the location of the higher pressure cylinder or cylinders through the main steam-supply pipe and thence forwardly ithrough a' relatively long receiver pipe at reduced pressure to the low pressure cylinder or cylinders.; j i i Another object is to provide an engine of the e character last described wherein the low pressure cylinders, their distribution valve chests, and a `casing for the yintercepting valve means are formed as aunitary structure.

Another object is to provide a triple expansion engine embodying' a receiver pipe between its higher pressure cylinders and low pressure cylinder or cylinder for delivering steam exhausted thereto from said higher pressure cylinders tothe low` pressure cylinder or cylinders for operating the low pressure cylinder or cylindersduring triple expansion operation of the yengine and adapted to serve as a passage to the atmosphere for nal exhaustlsteam of the higher pressure cylinders at certain times` when the engine is working single expansion of a majority of the cylinders; Y -5 Anotherobject is to provide a multiple expansion engine having steam distribution apparatus embodying valve means operable to insure a substantially constant and adequate amount of back pressure'for the higher pressure cylinder 10 or cylinders whenthe low pressure cylinder or cylindersiis being operated by live steam and the steam finally exhausted from the higher pressure cylinder or cylinders is being delivered to the atmosphere. y f 15 Another object is to provide an improved valve designed so as,` to particularly adapt it for use as a back pressure valve for the purpose aforedescribed.

' Another object is to provide a multiple ex- 20 pansion engine embodying steam distribution apparatusincluding intercepting valve means embodying valve means for delivering steam` inally exhausted from the higher pressure cylinder 0r cylinders to the atmosphere during operation of the `low pressure cylinder or cylinders by live steam, back pressure Valve means of the character aforedescribed and meanslfor manually simultaneously controlling the exhaust valve means and back` pressure valve means whereby, when the exhaust valve means is open to deliver iinally exhausted steam from the higher pressure cylinder or cylinders to the atmosphere, the back pressure valve means will be operated to insure a substantially constant and adequate amount of back pressure for the higher pressure cylinder or cylinders. Another object is to provide a triple expansion engine having steam distribution `apparatus of the general character aforementioned embodying reducingfeed valve means fory one orlmore of the engine intermediate or low pressure cylinders adapted to automatically effect delivery of live steam for said cylinder or cylinders when the pressure ofsteam being deliveredthereto is below a predetermined amount relative to the live steam pressure;

Anothergobject is to provide steam distribution apparatus of the character aforementioned embodying regenerator feed` valve means automatically operable for closing and manually controllable for opening to eiect when open delivery of live` steam to augment other steam being delivered for the operation of the cylinder or cylinders of low pressure.

Another object is to provide improved reducing valves especially adapted for use as parts of the valve means aforedescribed.

Other and further objects of and advantages achieved by this invention will be apparent from the following description of an approved embodiment thereof and the appended claims.

The invention is illustrated in the accompanying drawings wherein Figure 1 is a horizontal Central sectional view through the working cylinder valve chests of a triple expansion engine embodying the apparatus of the present invention with. the several valves of the apparatus also shown in horizontal central section, certain parts being broken away and other parts being omitted and the valves of the apparatus' being shown in positions for single expansion engine operation of a majority of the cylinders; Fig. 2 is a horizontal central sectional view of the reducing feed valve and adjacent parts, for the intermediate pressure cylinder, shown in Fig. l, with the valve shown in open or starting position; Fig. 3 is a horizontal central sectional view of the regenerator valve and adjacent partsshown in Fig. 4, with the valve shown in open position; Fig. 4` is a view similar to Fig. l, with certain parts shown in Fig. 1 omitted, showing the various valves of the apparatus of the present invention in positions for normal triple expansion engine operation; Figs. 5 to 8 are enlarged detail views of the structure shown in Fig. 2, Fig. 5 being a horizontal sectional view, Fig. 6 a front end view, Fig. 7 a half rear end View, and Fig. 8 a half side View; Figs. 9 to 12 are enlarged detail views of the structure shown in Fig. 3, Fig. 9 being a side View, partly in section, Fig. l a horizontal section on the line X-X of Fig. 9, with the discharge pipe shown kfragrnentally in plan, Fig. 11 a transverse section` on the line XI--XI of Fig. li), and Fig. 12 a front end view; Fig. 13 is an enlarged horizontal central sectional view of the back pressure Valve, separate exhaust Valve, intercepting valve, and reducing feed Valve forthe low pressure cylinders, shown in Fig. 1, a part being broken away; Fig. 14 is a section on the line XIV-XIV of Fig. 13; Fig. 15 is a section on the line XV-XV of Fig. 13; Fig. 16 is an end view of one of the valve elements of the intercepting valve, viewed from the right in Fig. 13; Fig. 17 is a section on the line XVII-XVII of Fig. 13. Figs. 18 and 19 are diagrammatic fragmental longitudinal views on a reduced scale of a locomotive embodying the features of the present invention, said features being shown principally in vertical section taken on the broken line KIEL-XVIII, Fig. 1, Fig. 18 showing the front end half of the locomotive and Fig. k19 the rear end half of the locomotive, for the purpose of `clarity certain of the piping connections being shown in these figures in slightly different positions than those in Iwhich they are shown in other of the figures; Fig. 20 is a vertical sectional view of the manual control Valve for the back pressure and separate exhaust valves; and Fig. 21 is an end View of the valve shown in Fig. 20.

In compound engines the piston of a high pressure cylinder is actuated by direct admission of boiler or live steam and the piston of a low pressure cylinder is actuated by steam exhausted from the high pressure cylinder during normal or compound operation and the pistons of both the high and low pressure` cylinders are actuated by direct admission of boiler or live steam for operation of the engineas a singlerexpansion engine.

In triple expansion engines an intermediate pressure cylinder is employed and during normal or triple expansion operation the piston of a high pressure cylinder is actuated by boiler or live steam, the piston of .an intermediate pressure cylinder is actuated by steam exhausted from the high pressure cylinder and the pistons of the low pressure cylinders are actuated by steam exhausted from the intermediate pressure cylinder, and all or a majority of the cylinders are operated by live steam during single expansion operation of all or a majority of the cylinders.

While many of the features of the present invention are applicable for use in both compound and triple expansion engines, in the following description an approved embodiment of the present invention is described adapted for a triple expansion engine.

The working cylinders of the locomotive embodying the invention which is illustrated in the accompanying drawings include a high pressure cylinder l, an intermediate pressure cylinder 2 oppositely disposed to the high pressure cylinder, and a pair of oppositely disposed low pressure cylinders 3 and 4 spaced forwardly of the cylinders I and 2 respectively. Each of these cylinders is provided withy distribution and exhaust valve chests, and distribution and exhaust poppet valves of the usual well-known type are disposed in the respective valve chests. The poppet valves of the valve chests of the high pressure cylinder i only are shown, see Fig. l. It will of course be understood, however, that the valve rchests of each of the cylinders 2, 3 and 4 are similarly provided with poppet valves. These poppet valves include inlet valve elements and exhaust Valve elements 6 and their construction, arrangement and operation are of the usual well-known type, see for instance patent issued to J. Kupka, No. 1,638,736.

The high pressure working cylinder and the intermediate pressure working cylinder, their respective distribution valve chests, and a receiver 1 are all formed in a one piece integral casting, the receiver being disposed between the two cylinders and their valve chests.

A live steam feed pipe 3 is connected at one of its ends with the engine boiler (see Fig. 18) for receiving steam therefrom, and at its opposite end the pipe is separated into two branch pipes 9 and i. The branch pipe 9 extends forwardly and is connected for delivery of live steam for the low pressure working cylinders for operation thereof either during their single expansion operation or as an auxiliary supply, as hereinafter more fully described. The branch pipe it) is connected -with the inlet valve chests of the high pressure working cylinder i for the delivery of steam thereto in the usual manner. At each of the exhaust valve chests of the cylinder I an exhaust passageway ii is formed leading from the respective exhaust ports ta of the Valve chests to the receiver l. During operation of the engine the exhaust steam fromthe cylinder i will be delivered through these p-assageways i i to the receiver l. A passageway i2 is also connected with the branch pipe i@ and passes under the exhaust valve chest at the rear end of the cylinder i to a' feed reducing valve i3. It will be understood that where the phrase live steam is used in this description and in the appended claims it is intended to mean steam taken directly from the boiler, that is steam which has not been used for the operation of a working cylinder. y

The feed reducing valve I3- shown in detail in Figs. 5 to 8` (also shown in Figs. 1, 2 and igt-hose' views being on too small a scale to show all of the details), comprises a body or casing I4 which is mounted on the rear'end of the receiver 'I over an opening i5 Aformed therein,l the v-alve I3 being suitably secured tothe receiver by studs (not shown). The body portion I4 includes a cylinder i5. `A pair of spaced annular ports Il and i8 is formed in the cylinder near the front end thereof. The portion ofthe cylinder I6 forward of the port Il is of a slightly greater diameter than the portion of the cylinder to the rear thereof. An annular passageway IS is formed around the cylinder in communication with the port il, and va passageway 2l) is formed at one side of the casing I4. The port I1 opens into and the passageway I9 merges with the passageway 2d. The passageway 20 is connected with the passageway l2 for receiving live steam therefrom. The port i8 is curved and extends 'outwardly and forwardly opening into; the `receiver l through the opening I5.

A sleeve 2l is disposed within the cylinder I 5 and is adapted for reciprocation therein, suitable packing rings 22 being provided around the sleeve 2| between its outer wall and the inner wall of the cylinder it to insure a Vsteam-tight engagement therebetween. Corresponding to the variation in the diameter of the cylinder, the forward portion of the sleeve 2| is of slightly greater diameter than the portion to the rear thereof so as to put the ports Il and I3 in communication with each other when the sleeve is in its forward or open position as shown in Figs. 2 and 5. A

, circumferential groove 23 is formed in the outer wall of the sleeve 2l at the rear of the forward portion thereof. The groove 23 increases the opening between the ports il and I8 when the sleeve 2E is in its forward or open position, this being the open position ofthe valve I3 for delivery of live steam to the receiver 'I whenl starting `the locomotive in operation. f When the sleeve 2| is moved rearward from the position shown in Figs, 2 and 5 to the position shown-in Fig. 1, the ports Il andV I8 will be closed;v that is, held out of communication by the portion of the sleeve 2| of larger diameter, and the direct delivery of live steam to the receiver 'I will be prevented.

A hollow stem 24 is disposed through the cylinder IE5 and `sleeve 2l. The steam 24 extends through an opening 25 formed inthe rear end of the casing i4. A shoulder 2S formed on the stem 24 abuts the inner wall of the casing around the opening'll anda nut 2'! threadedly engages the outer `end` cf the stem and holds the stern securely in position. The stem is of such diameter as to have a working clearance within the i sleeve 2l, and suitatble packing rings 28 are `pro- Vhead 29 when the sleeve is in its forwardmost position, the forward movement of the `sleeve 2I being thus limited.` A passage ita is formed at i the rear end ofthe cylinder-I5forfopening the space behindA the sleeve. 2l to theatmosphere.

Also suitable passageways 3l are formed in the stem 24 and sleeve 2 I. These' p-assageways serve to minimize the passage of steam, which has leaked past the packing rings 2?` andr 28 at the r'Ihe unbalanced surface of the sleeve indicated at 32 against which live steam from passageway 20 is adapted to exert pressure and theunbalanced surfaces of the sleeve indicated at 33 against which steam within the receiver 'i is adapted to exert pressure are so proportioned as to affect a sleeve which will be moved rearwardly to closed position when the pressure within the receiver is increased a predetermined amount relative to the pressure in the passageway 2U and the sleeve will be moved forwardly to open position when the pressure within the receiver is below that predetermined relative amount. The ratio will be xed so-that the valve will be opened when the amount of pressure within the receiver is below the amount necessary for the proper operation of the intermediate working cylinder 2, which is the case in starting, and will be closed when the pressure is at or above that amount.

1t will thus be apparent that the operation of the valve I3 is entirely automaticand that normally the steam for the intermediate working cylinder 2 will be supplied yto the receiver 'l through the passageways iI, that is', only the steam exhausted from the high pressure working cylinder i will be normally used for the operation of the cylinder 2. Duringthe starting of the'locomotive however the intermediate cylinder willalways be operated for at least a few reciprocations by the aid of live steam admitted through 'valve I 3, that is, it will `be so operated until the steam pressure within the receiver 'i is lbuilt up and sufficient exhaust steam from the cylinder l is supplied through the passageways II for the operation of the intermediate cylinder byexhaust steam as aforedescribed, and thereupon the valve i3 will automatically close.

The exhaust passageways 34 of the valve chest of theintermediate pressure cylinder 2 are connccted to a passageway 35 integrally formedwithin the chamber 'I and extending forwardly therefrom. A receiver pipe' 35 is connected to the forward end of the passageway 35 and extends forwardly for delivery of steam exhausted from the intermediate pressure cylinder 2 for the operationfof the low pressure cylinders 3 and ll.

A back pressure valve 3l" is disposed at the forward end of the receiver pipe 36, see particularly Fig. i3. One of the p-urposes'of this valve is to maintain a sufficient amount of back pressure against the intermediate pressure cylinder piston, during simple or single expansion operation onlyA cfa majority `of the cylinders, to maintain the-proper balance of work. The valve 3l comprises an outer cylindrical' casing 38 which is concentric with the pipe 3S. For the purpose of facility in assembling, the casing 38 is made in two separate portions, a rear portion 49 and a forward portion Kil. The portions 423 and 4I are provided with circumferential flanges 42 which are suitably connected together by bolts (not shown). .The portion 4G is slidably connected at its rear end to the forwardv end of the pipe d6 in a well-known manner, a suitablepacking gland 39 being provided to insure a steam-tight connection. At the forward end of the portion 4I a circumferential flange G3 is provided and is suitably connected by bolts (not shown) to a similar flange formed around an opening 44e formedin a wall of a receiver 44, a. joint ring 45 being interposed between the flanges.

Within the casing portion Ml an inner cylinder 4S is centrally disposed, providing an annular passageway il therearound between its outer surface and the inner surface of the casing portion All. The cylinder 46 is integrally formed with the casing portion d and is suitably held in place by radial webs 48. A closure 49 is provided at the forward end of the cylinder l5 and an opening t is centrally formed in the closure 4.19.

In the casing forward portion lll a cylinder 5l is centrally disposed. This cylinder is formed integrally with the portion il and is secured thereto and held in place by suitable webs 52. The cylinder 5l is closed at its front end by a head 53 and a pipe or passageway 5t leads from the interior of the cylinder 5| at the forward end thereof, to the outside of the casing portion di. The cylinder 5l is open at its rear end.

Centrally disposed within the casing 38 is a piston rod 55. Upon the rear end of the piston rod 55 acylindrical valve element 55 is secured by suitable webs 56a. When in closed position, as shown in Figs. l and 13, the valve element 55 is adapted to extend over the rear open end of the annular passageway il closing this end of the passageway. The valve element is longitudinally movable to open position as shown in Fig. 4, in which open position the rear end of the passageway al is open permitting steam to iiow freely through the passageway li around the cylinder d5. A valve disc 5l is secured on the piston rod 55 at the central portion thereof. The disc 51 is adapted when the valve element 55 is in closed position, as shown in Figs. 1 and 13, to substantially close the opening 5i) so that steam passing through the valve will be restricted a predetermined amount, and when the valie element 56 is in open position, as shown in Fig. 4, the disc 5l will leave the opening 5D substantially unrestricted for the passage of steam therethrough as well as through the passageway lil.

An operating piston 58 is secured at the forward end of the piston rod 55 and is reciprocably disposed within the cylinder 5|. A pipe 59 is con'- nected to the passageway 5t and extends to a three-way manually controllable valve 55a (see Figs. 20 and 21) of usual construction located in the cab of the locomotive indicated generally by the reference character A. One of the ways or connections oi the valve 59a is connected by a pipe 59h to the steam drum of the boiler and another of the Ways is connected to a pipe 59C which leads to the atmosphere, the pipe 59 being connected with the third way and thereby being adapted to selectively be brought into communication with the steam boiler or with the atmosphere when the plug or valve element 59d of the valve is appropriately turned. Thus when the valve element 59d is turned so as to connect the pipe 5S and passageway 54 with the boiler, steam will enter the forward end of the cylinder 5l and force the piston 58 rearwardly so as to close the valve 3l, that is, bring the valve element 56 over the rear end of the passageway or port 4l and bring the disc 51 into a position partially closing the opening 5l).

The pressure required to open the valve 3l', that is, force the disc 51 away from the opening 5U will be equal to the operating or boiler pressure divided by the ratio of the area of the valve disc 5l which is subjected to the steam pressure of the pipe 36 to the area of the piston 5B which is subjected to pressure within the cylinder 5l plus the small amount of pressure at the forward side of the disc 5l. It will be apparent that this back pressure will be constant for various pressures of steam delivered through the pipe 36 as long as the operating pressure which is delivered to the .1

cylinder 5l is constant, that is, a predetermined back pressure will be maintained although the outow of steam from the intermediate pressure cylinder varies.

The receiver 411 heretofore mentioned is disposed between the valve chests of the low pressure cylinders 3 and il, and these valve chests, the receiver ill and the low pressure cylinders are all formed as an integral one-piece casting. Inlet ports 50 are formed at each of the inlet valve chests and are in communication with the receiver t4 for receiving steam therefrom for operating the low pressure cylinders. The exhaust passageways of the exhaust valve chests lead to the atmosphere in the usual manner.

An intercepting valve device indicated generally by the numeral 62 is provided in connection with the receiver 44. IThe intercepting valve device includes a separate exhaust valve 63, an intercepting valve proper 54 and a reducing feed valve 65, see particularly Fig. 13. A casing 56 is formed in the rear portion of the receiver 4Q for the separate exhaust valve 63 and intercepting valve proper 54. A passageway 67 is provided in the casing 56, the rear end of this passageway opening at the rear of the receiver All, in communication with the front end of the back pressure valve 3l through the opening lila formed in the wall of the receiver 64, for receiving steam delivered from the intermediate pressure cylinder 2..

Walls 68 and 58a, are integrally formed with the casing 65 providing chambers 69 and l'EI separate from the passageway 6'! and the remainder of the receiver M. The chambers 69 and i6 are in communication with each other through an opening 'H formed in the wall 68 between these chambers. An opening 'l2 is also formed in the wall 58a for providing communication between the chamber 'lll and the forward end of the passageway 67. An opening 'I3 is provided in the rear wall of the receiver Ml for a purpose hereinafter described and an opening 'lll is formed in the front wall of the casing 65 for providing communication between the passageway 61 and the receiver @Il exterior of the casing 66. The openings il, 12, 'i3 and l are all in alignment. with each other. An opening 'i5 for a purpose hereinafter described is provided in the front wall of the receiver M, also in alignment with the openings 'H .to 'M A valve casing 'I6 is provided at the rear end of the receiver lli and comprises a cylindrical body portion Tl which extends through the opening i3 into the chamber 69, a cover 'i8 which closes the rear end of the body portion and is secured tor the rear wall of the receiver Vfifi around the opening 'I3 by studs (not shown), and a hollow neck 'I9 which extends outwardly from the cover. The neck isin communication with the interior of the body portion through an opening 'd8a formed in the cover. A stem 8D is extended through the neck and body portion and is adapted for reciprocation therein. A head 85a is provided on the outer end of the stem SG at the outside of the neck and is secured thereto by a nut 8l. A helical spring S2 is disposed around the neck 'F9 and bears at its forward end against the cover 'E8 and at its rear end against the head 80a so as to resiliently tend to force the stem 80 rearwardly.

At the forward end of the stem 80 the separate exhaust valve 63 is secured. 'Ihe separate exhaust valve 63 surrounds the stem 80 and comprises a cylindrical body portion 84, a piston 85 formed at its rear end, and arvalve disc formed at its forward end. The piston operates within the cylindrical portion Tl.j The disc 86 isadapted, wheny the valve E3 is in its rearwardmost or closed position, as shown in Fig. 4, to rest upon arseat formed around the opening ll andto close this opening. A port 81 is formed in the cover 18 and a pipe 88 is connected at one of its ends to said port and at its other end to the pipe 59 afore- `described. Steam is introduced into and cxhausted from the interior of the cylindrical portion 'Il by manipulations of the valve 59a, at the same times and in the same manner as described with reference to the cylinder 5|. Thepressure of this steam, boiler pressure, will be suflicient to hold the valve 63 in open positiomas shownv in Figs. 1 and 13, against the force of the spring 82` and when the steam is exhausted from the cylindrical portion 'l1 the force of the spring will move the valve 63 rearwardly and bring thevalve disc 86 back upon its seat, closing the opening as shown in Fig. 4. The chamber 99 is connected by a suitable passageway 89 to the engine exhaust pipe 89a which of course is in communication with the atmosphere through the stack 89b in the usual manner. 1

, Thus it will be apparent that the opening of valve disc 98 will permit steam from the chamber 10 to pass to the atmosphere through opening 1|, chamber 09 and passageway 89 and therebyeffect movement` of the unbalancing valve 92, hereinafter described, to full open positiornwallowing comparatively free flow of steam from passageway S1 through the opening l2 andthence as just described to the atmosphere. A valve disc |09, hereinafter` further described, is provided for the opening '|4. A valve stern 9,0 is provided for the unbalancing valve 92, the valve disc |90 and the reducingfeed Valve 65. An annular flangev 9| isformedaround the opening l2 in the wall 98a. The annular unbalancing valve 92 is disposed within the flange 9| and adapte to reciprocate therein. v

The valve 92 (see particularly Fig. 13) comr prises a conically shaped plate 93, a hub 94 formed centrally of the plate and an outer annular wall around the hub 'spaced forwardly ofthe outer periphery of the plate so as to provide in effect an annular port 99. The hub 94 is connected by webs 91 with the plate 93 and annular wall 95. The hub 94 is hollow and the rear end of the stem 99 is passed` therethrough, a nut 98 provided at the end of the stem V99 securing the valve 92 to theI stem. The annular port 96 permits the free pas--V sage of steam from the passageway El into 'the chamber l0 when the intercepting valve device is in the position shown in Figs. 1 and 13, while when the intercepting valve device is in open position, that is, that shown in Fig, 4, the port 95 is adjacent the flange 9i and thereby closed. Openings 9:9 are provided in the plate 93 and it will Vbe apparent that even in the closed position of the unbalancing valve92 steam will-pass through theopenings 99 into the chamber 10, and by `virtue of this ar-A rangement when the disc 86 has closed the port 1| a certain amount of pressure will be built up within the chamber '19. Thus when the separate exhaust valve 63 is in closed position and the disc |00 is open the valve 92 will have no disturbing effect upon the disc |00. Also the value 92 acts to effect a quick closing of the discA |00 when steam is exhausted from the chamber 19 to the atmosphere by reason of the rapid decrease in pressure on the rear side of the valve 92 relative to the pressure on the forward side thereof.

The stem 90 passes centrally through the disc |00 and is provided with a collar |0| which abuts the front surfacel of the disc |00 while a nut |92 threadedly engages the stem 99 at the rear side of the disc |09 forcing the disc against the collar and securing A,it to thegstem. When the intercepting valve device 62 is in closed position, as

in Fig. 4, the passageway El is open to the interior of the receiver 44 exterior of the casing 96 for supplying steam exhausted from the intermedia-te pressure cylinder for operating the low pressure cylinders.

Afvalve, casing |93 is disposed at the forwardend of the, receiver 44 at the outside thereof, over the opening l5. The casing |93 is shaped similar tothe casing 4 of the valve I3, beingr4 provided with a cylinder or bodyportion |94 which is open at its rear end opposite to the opening l5. The casing |03 is suitably secured to the receiver by studs (not shown)k passed through a circumferential flange formed on the rear end of the cylin-A der |94 and extended into the receiver wall around -the opening l5. A cylinder |95 of larger diameter than the1 cylinder |94`is disposed at the forward end of the cylinder |04, and a wall |99 joins the two cylinders, which are open to each other at their adjacent ends.

An annular passageway |91' is formed around the cylinder |04 and an inlet passageway |98 connects and merges with 'the passageway |91. A pair ofspaced annular ports .l 09 and l I9 is formed in the cylinder |04. The port |09 extends outwardly-or radially and rearwardly, opening` into v the receiver 44. The port'I 0 extends outwardly or radially and forwardly, opening into the annular passageway |91 and the passageway |98. Similar to the cylinder I6 of the valve i3, the portion of the cylinder |94 rearward of the port ||0 is of a slightly greater inner diameter than the portion of the cylinder forward thereof. A sleeve is fitted in the cylinder |94 and adapted for reciprocation therein. `Similar to the sleeve 2|, `the outer diameter of the forward portion of the sleeve is slightly less than the outer diam--` eter ofi-the rear portion thereof, corresponding to the difference in diameter of the forward and rear portions of the cylinder |94, so that when the sleeve is in its rearward or open position, as shown in Figs. l and1`3,'the ports |99 `and |10 will be in communication with each other.

The sleeve'is` provided with suitable packing rings between its outer surface and the inner surface of the cylinder |04 to insure a steam-tight fit. A circumferential groove H2 is formed in the outer surfaceof the sleeve I at the rearend of its forward portion. When the sleeve is in, rearward or open position the groove l2 increases the opening between the portsliiiand H9 so` that steam may pass freely from the passageway |08 to the interior of the receiver 44. The pas` sageway |98 is connected to the live steam branch pipe 9 for receiving steam for the operation of the low pressure cylinders at cerftain'periods as already stated. y

. will permit such position of the sleeve.

An enlarged hollow end-I I3 is formed at the forward end or the valve stem Se. The enlarged end I I3 rits within the sleeve II I and is adapted for longitudinal movement relative thereto. Suitable packing rings I |3a are provided between the end I I3 and sleeve I I I to insure a steam-tight t. An inwardly extending shoulder IIII is formed at the rear end of the sleeve III and an outwardly extending shoulder II5 is formed at the rear of the enlarged end IIS. These two shoulders are adapted for engagement with each other so that the sleeve is limited in its rearward travel.

The surface II Il of the end of the sleeve III and the portion of the shoulder I I against which steam within the receiver 44 is adapted to exert pressure, and the unbalanced surface of the sleeve against which steam from the pipe |08 is adapted to exert pressure, as indicated at I |'I, are so proportioned that when the steam pressure within the receiver 44 falls so that the ratio of the steam pressure within the receiver III to the boiler pressure or pressure of the steam within the pipe |08 is changed beyond a predetermined amount, steam from the pipe |08 will force the sleeve III rearwardly to open position, as shown in Figs. 1 and 13, provided of course the stem 9U is in rearward position so that the shoulder |I5 The pressure of the live steam will, however, be suicient to move both the sleeve III and stem 9|? rearwardly to open positions in the starting of the engine.

Passageways, indicated generally at II Ia are provided in the sleeve I II and in the enlarged hollow end IIS, and a passageway |2519 is provided in the cylinder |05. The passageways I I Ia correspond to the passageways 3| and the passageway |2517 corresponds to the passageway IBa in the valve I3. The purposes of the passageways I I Ia and Ib are the same as the purposes of the corresponding passageways in the valve I3, as herein'oefore described. The passageway Iilb also serves to relieve compression back of a piston head H8 hereinafter described.

When the steam pressure within the receiver 44 is built up, that is, rises so that the pressure ratio between the steam within the receiver 44 and the pipe |28 is changed beyond the said predetermined amount, due to the difference in the effective areas of the combined surfaces provided by the shoulder IM and that indicated at I I6, and the surface indicated at I IT, and the diiferent pressures acting thereon, the sleeve III will be forced forwardly to closed position, thereby cutting off the delivery of live steam through the valve 55 to the receiver 134. It will also be apparent that when the stem 92 is moved forwardly to the open position for the valve disc |00 aforementioned, due to the shoulders I III and I I5, the sleeve will be brought to and held in closed position, as shown in Fig. 4.

The piston head II8 is secured on the outer .end of the enlarged end I I3 of the valve stem 9i). The piston head IIS is adapted to reciprocate within the cylinder |05. A cover I05a is provided over the outer end of the cylinder |65. There is thus provided by the cylinder rI |35 a dash pot which will act to cushion the movement of the valve stem 9H and the several members secured thereto.

A regenerator live steam feed valve I I9 is provided at the forward end of the receiver 44 at one side of the feed valve 65. An opening |20 is provided in the wall of the receiver 44. A seat I2I is provided around the V'opening and a semi spherical hollow member |22 having a peripheral flange |23, extends into the opening with its flange bearing against the seat I2I. The member |22 is provided with a hollow inwardly exw tending neck |22 and an inlet pipe |25 is secured at its forward end in the neck |22. The pipe extends rearwardly in the receiver |512, is closed at its rear end with a cap |26 and is provided with a plurality of perforations I2'I permitting the passage of steam therethrough from the interior of the pipe into the receiver. The valve I I9 comprises a cylinder |28 formed at its rear portion to provide an annular passageway |29. The passageway I 29 extends radially inward at its rear end through the wall of the cylinder |28. A curved passageway IEIII is formed in the cylinder |28 to the rear of the passageway |29. The pas' sageway I3!! extends radially and rearwardly through the wall of the cylinder |23 opening into the hollow member |22. The inner diameter of' the portion of the cylinder |28 rearward of the passageway |29 is greater than the inner diameter of the portion of the cylinder forward of the passageway |29.

A sleeve ISI is disposed within the cylinder |28 and is adapted for reciprocation relative thereto, suitable packing rings |32 being provided between the outer surface of the sleeve and the inner surface of the cylinder to insure a steamtight t therebetween. Corresponding to the different inner diameters of the cylinder |28, the forward portion of the sleeve I3! is of less diameter than the rear portion thereof, so that the passageways |29 and |39 are in communication with each other when the sleeve I3I is in its rearward or open position as shown in Figs. 3 and l0. A circumferential groove |33 is formed in the outer wall of the sleeve I3I at the rear end of its forward portion, so that when the sleeve is in open position an increased opening will be provided between the passageways |29 and |39.

A port |36 is provided in the wall of the cylinder 28 in communication with the passageway |29. A port |35 is likewise provided in the wall of the casing |83 of the valve 65, the port |35 being in communication with the passageway IIII and hence with the passageway Iil and the pipe 9. A pipe |36 connects the port |32 with the port |35. It will be apparent that when the sleeve ISI is in the open position aforedescribed live steam will be permitted to pass from the pipe 9 through the valve IIQ into the receiver dll.

A hollow piston rod |37 is disposed within the sleeve ISI and adapted for reciprocation therein, suitable packing rings |32 being provided between the outer wall of the piston rod ISI and the inner wall of the sleeve I3! to insure a steam-tight fit therebetween. Passageways indicated generally at I3 Ia are provided in the sleeve ISI and the piston rod |37 and a passageway |28a is provided in the cylinder |28. The passageways I3I0. corre. Spond to the passageway 3| and the passageway |28@ corresponds to the passageway Ita in the valve I3. Thus these passageways ISIa and I28a in the valve H2 serve the same purposes as their corresponding passageways in the valve I3, as hereinbefore described. The passageway I28a also serves Vto relieve compression back of a piston head |41 on the rod I S'I and to provide communication with the atmosphere for the passageways I3 Ia at the front end of the piston rod IS'I.

An inwardly extending shoulder |39 is formed on the inner wall of the sleeve ISI near the rear end thereof and an outwardly extending shoulder |4ll is formed on the rear end-of the piston rod |31. The shoulder |39 is adapted to abut the shoulder i4!) limiting the rearward movement of the sleeve |3| relative to the piston rod,and when the piston rod H31 is in closed position, as shown in Fig. 1, serves 'to hold thesleeve in closed position so as to cut olf communication between the passageways E29 and |30. The piston urod |31 is hollow, to save weight, and is closed at its rear endby a plug |fli,`there being thus provided a relatively great area against which steam pressure at the rear of the piston rod |31, that is',`steam within the receiver 44, will act to forcethe piston rod |31 and consequently the sleeve |3| (if it isin open position) forwardly into closed position. An annularnward projection |42 is formed within the cylinder |28 spaced rearwardly from the forward end thereof. The inner diameter of the annular projection is the same as the outer diameter of the piston rod |31 and the piston ro-d is `adapted to move through the annular projection. i i 'Y The cover plate |43 is provided at theextreme forward end of the cylinder |28 thus providing a chamber |44. A port |45 is provided in the cover plate in communication with the chamber |44 and .in air pipe |45 is connected to the port |45. A piston head |41 is` secured to theforward end of the piston rod |31 and is adapted to reciprocate within the chamber |44, suitable pack- `ing rings `i455 being provided between the outer wall of the piston head |41 and the innerwalllof the chamber |44 to provide an air-tight t.

The pipe |46 leads to a manually controllable i `three-way valve 46d` which is similar inconstructio-n and operation to the valve 58a and is also located in the cab of the locomotive. `One way of the valve t45ol is connected by a pipe |4|b` to a compressed air container |460 and another wayof the valve connected to a pipe r |45@ which leads to the atmosphere, the third Way being connected to the pipe |45. By suitable operation of the valve Hita the pipe |46 may thus be selectively con` nected with the source of compressed air orcontainer 546e or with the atmosphere. Thus when compressed airis supplied to the pipe-|46 the piston head B41 is moved rearwardly permitting the. sleeve i3! to move to open position under suitable conditions.

The surface of the sleeve against which the steam pressure of the receiver 44 is" adapted to exert force, indicated at |49, and the surface f the sleeve against which the live steam from thel pipe 3 is adapted to exert force, indicated at |54, are so proportioned that with the piston rod $31 held in rearward position by the manuallycontrolled` air pressure in the chamber |44 aforedescribed, the sleeve l3| will be movedto open position by live steam in passageway |29 acting on the unbalanced area of the surface |54 against the resistance of receiver steam pressure on 'the surface |49, and therebyadmit the aforemen-` Y'tioned live steam `into receiver 44 Aat reduced` pressure. y Upon release of the air pressure from chamber E44 the `steam pressure inreceiver'llfl` `acting on the combined areas |49 and |49@ will force the sleeve |3l and piston rod |31 to closed `position against the live steam pressurein p assageway |29 acting on the unbalancedarea of the surface 58, and the sleeve will remain closedfas long as the aforementioned receiver pressure remains at or above a predetermined ,amountlcalled holding pressure, or until piston rod |31 is-manually lmoved rearward. In practice the regenerator (sometimes designated ac'celerator) valve 9 isdesigned so as to be controlled by a slightly lower minimum receiver pressure (holding pressure) than that maintaining the multiple (triple) expansion position of the intercepting Valve arrangement to avoid any tendency of tle regen-V v erator valve H9, that is to say the sleeve f3! and rod |31, toV lift and slam when the engine is thrown into single expansion operation of a mai jority of the cylinders by the manually controlled movement of the intercepting valve arrangement to a position corresponding to said single expansion operation.` r i In the operation of the engine for starting, steam will be delivered through the pipe 8 and branch pipe lll to the distribution valve chests of the high pressure cylinder and also to the feed valveA i3 and therethrough to the receiver 1 and from the receiver 1 to the distribution valve chests of the intermediate pressure cylinder 2, At the same time steam will be delivered through the branch pipe 9 and through the feedvalve G5 to the receiver 44 and from the receiver 44 to the distribution valve chests of the low pressure cylinders 3 and 4.

During this starting period the separate exhaust valve'63 will be closed. Also the intercepting valve disc Idil will be closed and the valve 32 will be open. l

Aftera few strokes of the working cylinders, when exhaust steam is being delivered through the passageways into the receiver 1, and pressure within the receiver 1 has been built up, the feed valve |3 will automatically close, and the intermediate cylinder 2 will thereupon be operated solely by exhaust steam from the high pressure cylinder. At this time pressure of the exhaust steam from the intermediate cylinder will have been built up at the rear of the intercepting valve disc suiciently to automatically open the intercepting valve disc. The feed valve 65 will be thereby closed unless it has been previously closed by the pressure in the receiver 44. The cylinders 3 and 4 will `thereupon be driven solely by exhaust steam from the intermediate pressure cylinder for triple expansion engine operation.

` If it is desired, however, to hold the engine in single expansion operation of a majority of the cylinders (i. e. operation by live steam of cylinders I. 3 and 4), thev separate exhaust valve 63 willbe, by its hand-controlled means, as aforedescribed, brought to open position. With the separate exhaust valve in open position steam from the receiver pipe 35, that is, intermediate pressure cylinder exhaust steam, will be exhausted to the atmosphere so that the intercepting valve disc Iil4 willbe held in closed position and the said single expansion operation of the low pressure cylinders will be continued. Inorder to permit Vthe engine to go into triple expansion operation, it will thereafter only be necessary to close the separate exhaust valve through operation of the valve 59a and" the engine will automatically go into triple expansion operation as aforedescribed. r

r If it isdesired to bring the engine into single expansion operation of a majority of the cylinders (i. e., operation by live steam of cylinders l; f

ders (operation by live steam of cylinders l, 3 and fl), and that in order to maintain this single expansion' operation the separate exhaust valve must be held open by the operator.

When the separate exhaust valve is closed the back pressure valve is always in open position permitting free passage of the exhaust steam through the receiver pipe to the receiver 44 for triple expansion operation of the engine as shown in Fig. 4. When the separate exhaust valve is held open the back pressure valve is always at the same time held substantially closed, as clearly shown in Fig, l. It will be apparent that by virtue of the location and function of the back pressure valve the pressure of the steam exhausted from the intermediate pressure cylinder will be held up to a predetermined amount back of the back pressure valve, also that, although the ful.1 volume of this exhaust steam is passed through the valve it will be released in more nearly a continuous flow and consequently at comparatively low pressure after leaving the back pressure valve.

Also, as it is unnecessary to restrict the separate exhaust passageway in order to provide back pressure, as was the case in intercepting valve arrangements heretofore used, the separate exhaust valve is ,so proportioned that the exhaust is comparatively free when the separate exhaust valve 86 is open. Furthermore, when this valve is manually opened to put the engine into single expansion operation of a majority of the cylinders, the back pressure valve disc 5l and valve element or sleeve 5S are also caused to move rearward, as previously described, thereby throttling the exhaust from the higher pressure cylinders, and at the same time limiting the exhaust container volume to be effected by the separate exhaust valve to the cavity represented by the passageway 6i, chamber 'l0 and receiver ltd, as well as also tending to lower the pressure therein. It is evident that this combination of imposed restrictions in the higher pressure cyiinders exhaust cavity, providing the above described re duction in the eective volume thereof and with the above mentioned free or Wide open separate exhaust when the exhaust valve 86 is opened, will result in a very rapid and deep drop in the exhaust cavity pressure behind the intercepting valve disc l0() and consequently cause a positive and quick movement of the intercepting valve device B2 to its position for single expansion operation of a majority of the cylinders. The necessity for this rapid drop in the exhaust cavity pressure when manually changing the engine from multiple (triple) expansion to single expansion operation of a majority of the cylinders will be understood from the following description.

The sleeve lll, forward end H3 of valve stem 9i), the associated parts of the reducing feed valve 55 of the intercepting valve device 62 must be designed so that the said valve 65 will be held closed against live steam (full boiler pressure) in vpassageway im by a pressure in the low pressure receiver M at, or preferably a little less than, the minimum receiver pressure when running the engine multiple (triple) expansion and at the shortest cut-off. Generally speaking the changing of the engine from multiple (triple) expansion operation to single expansion operation of a majority of the cylinders will not be required at the shorter cut-oils, but will be required at a time when the engine is working at maximum power (longest cut-off), and stillis unable to perform the work required, or in other words is about to stall. Consequently it will be obvious that, at the comparatively high receiver pressure involved by the long cut-oli, a very deep drop in pressure in the said cavity (passageway 61, chamber 'lll vand receiver Lili), together with a rapid rush of steam through the unbalancing valve 92, must be attained to eiect the desired movement of the intercepting valve disc lili! and feed valve 65 from multiple (triple) expansion positions to said positions for single expansion operation of a majority of the cylinders. This condition however could not be realized if the back pressure necessary against the exhaust of the intermediate cylinder was maintained throughout the passageway 8), chambers B9. and 'l0 and passageway 5l by a restricted separate exhaust outlet as was hereinbefore the practice.

It Will be apparent that the regenerator feed valve H9, the operation of which has been previously described, operates entirely independently of the other valves and that its function is to eiect an admission of live steam into the low pressure receiver to thereby raise the pressure within said receiver when desirable.

While there has been hereinbefore described an approved embodiment of the present invention it will be understood that many and various changes and modifications in form, structure and arrangement of parts may be made without departing from the spirit of the invention and it will be understood that all such changes and modifications as fall within the spirit of the invention as defined in the appended claims are contemnlated as a part oi this invention.

The invention claimed and desired to be secured by Letters Patent is:

l. In a triple expansion engine embodying a high pressure cylinder, an intermediate pressure cylinder and a low pressure cylinder, the combination of means for delivering live steam simultaneously to all o said cylinders for starting single expansion operation of said engine; means for delivering steam exhausted from said high pressure cylinder to said intermediate pressure cylinder for operating said intermediate pressure cylinder after said starting operation; means `for delivering steam exhausted from said intermediate pressure cylinder to said low pressure cylinder for operating said low pressure cylinder during triple expansion operation of said engine; means for automatically cutting o delivery of live steam to said intermediate pressure cylinder when said high pressure cylinder exhaust steam is sufcient for operation of said intermediate pressure cylinder; and means for automatically cutting off delivery of live steam to said low pressure cylinder when exhaust steam delivered from said intermediate pressure cylinder is suiicient for operating said low pressure cylinder.

2. In a triple expansion engine embodying a high pressure cylinder, an intermediate pressure cylinder and a low pressure cylinder, the combination of means for delivering live steam simultaneously to all of said cylinders for starting single expansion operation of said engine; means for delivering steam exhausted from said high pressure cylinder to said intermediate pressure cylinder for operating said intermediate pressure cylinder after said starting operation; means for delivering steam exhausted from said intermediate pressure cylinder to said low pressure cylinder for operating said low pressure cylinder during triple expansion operation of said engine; means for automatically cutting off delivery of live steam to said lintermediatepressure cylinder when said high pressure cylinder exhaust `steam is sucient for operation of said intermediate pressure cylinder; means fjorvautomatically cutting 01T delivery of live steam to said 10W pressure cylinder when exhaust steam delivered from said intermediate pressure cylinder is suiiicient ior operating said low pressure cylinder;

. and manually operated control means for hold- 1o ing the second said exhaust steam delivery means and the second said automatic means in positions continuing operation of said low `pressure cylinderby live steam and for adjusting `the second said-exhaust steam delivery means and the second said automatic means, to `change from triple `expansion operation of said engine to cperation of saidenginewith said low pressure cylinder operated bylive steam.

` 3. In a triple expansion engine embodying a 26" high .pressure cylinder, an intermediate pressure Cylinder and a low pressure cylinder, the combination of means for delivering live steam simultaneously to" all of said cylinders for starting single expansion operation of said engine; means for delivering steam exhaustedfrom said high pressure cylinder to said Aintermediate pressure cylinder for operating said intermediate pressure cylinder after said starting operation; means for delivering steam exhausted from said intermediate pressure cylinder to saidA loW pressure cylinder for operating said low pressure cylinder during triple expansion operation of said engine; means for automatically cutting off delivery or live steam to said intermediate pressure cylinder When said high pressure cylinder exhaust steam is sufficient for operation of saidfintermediate pressure cylinder; means for automatically cutting ofi delivery of live steam to said low pressure cylinder when exhaust steam delivered `from said intermediate pressure cylinder is suicient for operating said low pressure cylinder; and manually operated controlmeans, including separate exhaust means for delivering said; steam exhausted from said" intermediate pressure `cylinder to the atmosphere, for holding the second said exhaust steam delivery means land the second said automatic means in positions continuing operation of said 10W pressure cylinder;` by live steam and for adjusting the second said exhaust steam delivery means and the second said automatic means tochange from triple expansion operationfef said engine to operation of said engine with s aid low pressurecylinder operated by said `live steam. "Y

ll, In a triple expansion engine embodying a high pressure cylinder, an intermediate pressure cylinder and a low pressure cylinder, the combination of means for delivering live steam simultaneously to all of` said cylinders for starting single expansion operation of said engine; means for delivering steam exhausted from said high pressure cylinder to said intermediate pressure cylinder for operating said intermediate pressure cylinder after said startingoperation; means forv delivering steam exhausted from said intermediate pressure cylinder to saidloW pressure cylinder for operating saidlovv pressure cylinder during triple expansion operation` of said engine; means for automatically cutting off delivery of live steam to said intermediate pressure cylinder ,ting oi delivery of live steam to said loW pressure cylinder when exhauststeam delivered from said intermediate pressure cylinder is suiiicient for operating said 10W pressure cylinder; manually operated control means, including separate exhaust valve means for delivering said steam exhausted from said intermediate pressure cylinderto the atmosphere, for holding the second said exhaust steam delivery means and the second said automatic means in positions continuing operation of said low pressure cylinder by live steam and for adjusting the second said exhaust steam delivery means and the second said automatic means to change from triple expansionV operation. of said engine to operation of said engine with said low pressure cylinder operated by said live steam; and means for effecting a determined amount of back pressure of said steam being exhausted from said intermediate pressure cylinder when said separate exhaust valve means is delivering said steam exhausted from'said intermediate pressure cylinder to the atmosphere.

5. In a triple expansion engine embodyinga high pressure cylinder, an intermediate pressure cylinder and a low Apressure cylinder, the combination of means for delivering live steam simultaneously to all of said cylinders forestarting single expansion operation of said engine; means for delivering steam exhausted from said high pressure cylinder to said intermediate pressure cylinder for operating said intermediate pressure cylinder after said starting operation; means for delivering steam exhausted from said intermediate pressure cylinder to said low pressure cylinder for operating said low pressure cylinder during triple expansion operation of said engine; means for automatically cutting off delivery of live steam to said intermediate pressure cylinder when said high pressure cylinder exhaust steam is suiicient for operation of said intermediate pressure cylinder; means for automatically cutting off delivery of live steam to said low pressure cylinder Whenexhaust steam delivered from said intermediate pressure cylinder is suiiicient for operating said 10W pressuret cylinder; means for eiecting delivery o f said exhaust steam Vfrom said intermediate pressure cylinder to the atmosphere during operation of said engine with said low pressure cylinder operated by live steam; manually operated control means for.- said two 10W pressure cylinder steam delivery meansand said exhaust means adapted to permittripleexpansion operation of said engine or to electoperation of said engine with said intermediate pressure cylinder operated by said exhaust steam from said high' pressure cylinder and said lowlpress'ure cylinder operated by live steam; and 'back' pressure valve means simultaneously controllable by said manually operated control means for effecting a back` pressure or said steam being .exhausted from said intermediatepressure'cylinder when said steam is being delivered to the atmosphere.

6. In a-multiple expansion engine, the combination of an intercepting valve;` aseparate exhaust valve; a live steam feed valve,s aid separate exhaust'valve and intercepting valve being adapted for closed and open positions respectively'for the delivery of steam exhausted from a cylinder of higher pressure to low pressure cylinder feed means and'for open and closed positions respectively for directing said exhaust steam to the atmospheraand said live steam feed valve being adapted foran open position for "feeding live steam Ato'saidlovvr pressure cylinder feed Irreansf and for anclosed position for cutting off said feeding of live steam: and regenerator feed valve means adapted for an open position for feeding live steam to .said low pressure cylinder feed means to augment other steam fed thereto and for a closed position for cutting off said feeding o1'V augmenting steam.

'7. In a multiple expansion engine, the combination of an intercepting valve; a separate exhaust valve; a live steam feed valve, said separate exhaust valve and intercepting valve being adapted for closed and open positions respectively for the delivery of steam exhausted from a cylinder of higher pressure to low pressure cylinder feed means and for open and closed positions respectively for directing said exhaust steam to the atmosphere, and said live steam feed valve being adapted for an open position for feeding live steam to said.- low pressure cylinder feed means and for a closed position for cutting oi' said feeding of live steam; regenerator feed valve means adapted for an open position for feeding live steam to said low pressure cylinder feed means to augment other steam fed thereto and for a closed Vposition for cutting olf said feeding of augmenting steam; and means for manually controlling the operation of said regenerator feed valve means.

8. In a multiple expansion engine, the combination of an intereepting valve; a separate exhaust valve; and a back pressure valve, said separate exhaust valve and intercepting valve being adapted for closed and open positions respectively for the delivery of steam from higher pressure cylinder exhaust means to low pressure cylinder feed means and for open and closed positions respectively for the delivery of said steam from said exhaust means to the atmosphere and said backv pressure valve being adapted to open and close simultaneously with the closing and opening respectively of said separate exhaust valve to effect when closed a back pressure of steam in sai-d exhaust means when 'said steam is being delivered to` the atmosphere.

9. lIn a multiple expansion engine, the combination of' an intercepting valve; a separate exhaustA valve; a back pressure valve, said separate exhaust valve and intercepting valve being adapted; for closed and open positions respectively for the delivery of steam from higher pressure cylinderv exhaust means, to low pressure cylinder v feed means and for open and closed positions respectively for thedelivery of said steam from said exhaust; means to the atmosphere and said back pressure valve being adapted to open and close simultaneously with the closing and opening respectively of 'said' separate exhaust valve to effect .J annular passageway therearound within said caswayl and a disc movable with said annular element to. open andI closed positions for respectively fully opening one of said ends of said cylinder when said annular passageway is. open and partially closing saidy end tov restrictA the passage of steam through said cylinder when said annular passageway is closed.

1l. A back pressure valve comprising a cylindrical casing adapted to receive steam at one end and to emit steam from its opposite end; a cylinder disposed within said casing providing an annular passageway therearound within said casing, said cylinder being open at its opposite ends; valve means comprising an annular element movable to open and closed positions for respectively opening and closing said annular passageway and a disc movable with said annular element to open and closed positions for respectively fully opening one of said ends of said cylinder when said annular passageway is open and partially closing said end to restrict the passage of steam through said cylinder when said annular passageway is closed; and manually controlled means for said valve means for moving said annular element and disc to closed position.

l2. A back pressure valve comprising a cylindrical casing adapted to receive steam at one end and to emit steam from its opposite end; a cylinder disposed within said casing providing an annular passageway therearound within said casing, said cylinder being open at its opposite ends; valve means comprising an annular element movable to open and closed positions for respectively opening and closing said annular passageway and a disc movable with said annular element to open and closed positions for respectively fully opening one of said ends of said cylinder when said annular passageway is open and partially closing said end to restrict the passage of steam through said cylinder when said annular passageway is closed; and manually controlled means for said valve means for movingsaid annular element and disc to closed position comprising a cylinder within said casing, a piston reciprocably disposed within said cylinder and connected with said annular element and disc, and means for introducing and exhausting fluid into and from said cylinder to effect movement of said piston.

13. A steam distribution control apparatus for a multiple expansion engine comprising means for delivering live steam for operating cylinders of the engine during single expansion engine operation; means including receiver means, a separate exhaust valve and an intercepting valve, for delivering steam exhausted from one of said cylinders to a second cylinder for operating said second cylinder during multiple expansion engine operation and for delivering said exhaust steam to the atmosphere during operation of said second cylinder by live steam, the live steam delivery means for said second cylinder and said intercepting valve being adapted for automatic operation when the supply of exhaust steam is sufcient for operating said second cylinder, to cut off said supply of live steam to said second cylinder, and said separate exhaust valve and intercepting valve being adapted to be manually controlled for eifecting delivery of said exhaust steam to the atmosphere to effect said operation of said second cylinder by live steam; and a back pressure valve in said receiver means adapted to restrict the passage of said exhaust steam therethrough when said exhaust steam is being delivered to the atmosphere.

le. A multiple expansion engine comprising at least one higher pressure cylinder; a pair of lower pressure cylinders disposed forwardly of said higher pressure cylinder; distribution valve chests for each of said cylinders; means for delivering live steam to each of said valve chests for single expansion operation of said engine; means for delivering steam exhausted from said higher pressure cylinder to said lower pressure cylinder valve chests for operating said lower pressure cylinders; and valve means interposed in the two delivery means for said lower pressure cylinders adapted for automatic operation when the supply of said exhaust steam is sufiicient for operating said lower pressure cylinders to cut oil` said delivery of live steam tosaid lower pressurercylinder valve chests and to be manually controlled for electing delivery of said exhaust steam to the atmosphere to effect or maintain saidoperation of said lower pressure'cylindersby live steam, said valve means being interposed between said two lower pressure `cylinders and including a steam receiver for receiving said live steam andsaidexhaust steam and for the delivery thereof to the distribution valve chests of said lower pressure cylinders.

15. A multiple expansion engine comprising at y least onehiffher pressure cylinder; a pair of lower pressure cylinders disposed forwardly of said higher pressure cylinder; distribution Valve chests for each of said cylinders; means for delivering live steam to each of said valve chests for single expansion operation of said engine; means for delivering steam exhausted from said higher pressure cylinder to said lower pressure cylinder valve chests for operatingsaid lower pressure cylinders; andvalve means interposed in the two delivery means for said lower pressurecylinders adapted for automaticvoperation when the supply of said exhaust steam is sufficient for operating` said lower pressure cylinders, to cut oi said delivery of live Steam to said lower pressure cylinder valve chests land to be manually controlled for effecting delivery of said exhaust steam to the atmosphere to effect or maintain` said operation of said lower pressure cylinders by live steam, said valve means beingl interposed between said two lower pressure cylinders and including a steam receiver for ree ceiving said live steam, and said exhaust steam and for the delivery thereof to the distribution valve chests of said lower pressure cylinders and said lower pressure cylinders, their said valve chests and said receiver being formed as an integral casting.

, i6. A multiple expansion engine comprising at least one higher pressure cylinder; a pair of lower pressure cylinders disposed forwardly of said higher pressure cylinder; means, for delivering live steam for operation of each of said cylinders; meansincluding a `receiver pipe for delivering steam exhausted from said higher pressure cylinder to the atmosphere and to said lower pressure cylinders for operating said lower pressure cylinders; valve means connected with the two delivery means ior said lower pressure cylinders adapted for automatic operation when the supply of said exhaust steam issuiiicient for operating said lower pressure cylinders to out off said delivery oi live steam for said lower pressure cylinders and to be manually controlledto effect or maintain operation of said lower pressure cylinders by live steam, said valve means being interposed between said lower pressure cylinders and including a steam receiver and said receiver pipe being connected with said higher pressure cy1in der and'with said receiver; and a back pressure valvedisposed in said receiver pipe manually controlled to effect back' pressure of said exhaust steam from said higher pressure cylinder when said exhaust steam'is being deliveredto the atmosphere.

17. In alocomotive a multiple expansion steam engine comprising a low pressure cylinder in the proximity of the smoke stack; a higher pressure cylinder disposed in spaced relation to said low pressure cylinder at the rear thereof; a steam passage extending forwardly from said higher pressure cylinder to said low pressure cylinder for conveying exhaust steam from said higher pressure cylinder to said low pressure cylinder for operating same; intercepting valve means at the forward end of said steam passage; and means connecting the intercepting valve means with the locomotive smoke stack.

18. Inan engine, the combination of a working high pressure cylinder; means for supplying working live steam to said high pressure cylinder; a working intermediate pressure cylinder; means forisupplying working exhaust steam of said high pressure cylinder to said intermediate pressure cylinder; valve contained means for supplying working live steam to said intermediate pressure cylinder when the valve is open and for cutting off the live steam supply when said valve is closed, said valve having valve opening and valve closing control means adapted to be actuated to valve open and valve closed positions by fluid pressures, said control means being adapted for subjection to the influence of the pressure of said live steam tending to actuate said `control means to lvalve open position and for subjection to the pressure of said exhaust steam tending to actuate said control means to valve closed position, said control means being adapted for actuation to either of said positions by the corresponding Vactuating fluid pressure when at a predetermined preponderating amount relative to the other actuating fluid pressure whereby said intermediate pressure cylinder may be supplied with said live steam orfwith said exhaust steam only; a workinglow pressure cylinder; means for supplying working exhaust steam of said intermediate pressure cylinder to said low pressure cylinder; and a second valve contained means for supplying working live steam to said low pressure cylinder when the valve of said second means is open and for cutting off the live steam supply to said low pressure cylinder when the second said valve is closed, the said second valve having valve opening and valve closing control means adapted to be actuated `t`o valve open and valve closed positions by fluid pressures, the second said control means being adapted for subjection to the influence of the pressure of said live steam tending to actuate the secondsaid control means to valve open'position and for subjection to the pressure of said exhaust steam of said intermediate pressure cylinder tending to actuate the second said control means to valve closed position, the second said control means being adapted for vactuation to either of its said positions by its corresponding actuating fluid pressure when at a predetermined pre ponderating amount relative to its other actuating iluid pressure whereby said low pressure cylinder may be supplied with said'live steam or with said exhaust steam of said intermediate pressure cylinder only.

19. In an engine, the combination of a working high pressure cylinder; working live 4steam to said high pressure cylinder; a working intermediate pressure cylinder; means for supplying working exhaust steam of said high pressure cylinder to said intermediate pressure cylinder; a working low pressure cylinder; means for supplying working exhaust' steam ofA said in termediate pressure cylinder to said low pressure means for supplying` sti-1 cylinder; valve contained means for supplying working live; steam to said low pressure cylinder when the valve is open and for cutting oi the live steam supply when said valve is closed, said valve having valve opening and valve closing controlv means adapted to be actuated to valve open and valve closed positions by fluid pressures, said control means being adapted for subjection to the influence of the pressure ofk said live steam tending to actuate said control means to valve open position and for subjection to the pressure of said exhaust steam of said intermediate pressure cylinder tending to actuate said control means to valve closed position, said control ,1 means beingadapted for actuation to either of said positions by the corresponding actuating fluid pressure when at a predetermined preponderating amount relative to the other actuating fluid pressure whereby said low pressure A cylinder may be supplied with said live steam or with said exhaust steam only; manually controlled means for reducing said pressure tending to actuate said valve control means to valvev closed position whereby said Valve control means g, may be actuated by said live steam to valve open position or may be held in valve open position during the period of' said manual control; and manually controlled intermediate-pressure-cylinder-exhaust-steam back-pressure-providing valve means disposed between said pressure reducing means and said intermediate pressure cylinderv whereby said back pressure may be provided during said steam pressure reduction.

20. In a. multiple expansion engine, the combination of a low pressure steam working cylinder; a higher pressure steam working cylinder; means for feeding working steam to said higher pressure cylinder; a passageway for ieeding exhaust steam from said higher pressure cylinder to said low pressure cylinder; means disposed in said passageway for diverting said exhaust steam therefrom to prevent said exhaust steam from reaching said low pressure cylinder; means disposed in said passageway between said diverting means and said higher pressure cylinder comprising a valve adapted to eiect exhaust steam back pressure for said higher pressure cylinder during said exhaust steam diversion; and means i'or feeding working steam to said low pressure cylinder for op-erating said low pressure cylinder during said exhaust steam diversion.

21. In a multiple expansion engine, the combination of a low pressure steam working cylinder; a higher pressure steam working cylinder; means for feeding working steam to said higher pressure cylinder; a passageway for feeding exhaust steam from said higher pressure cylinder to said low pressure cylinder; means disposed in said passageway for diverting said exhaust steam therefrom to prevent said exhaust steam from reaching said low pressure cylinder; a valve having a fluid controlled valve element disposed in said passagewayV between said diverting means and said higher pressure cylinder for yieldingly restricting said passageway 1 to effect exhaust steam back pressure for saidhigher pressure cylinder during said exhaust steam diversion; and means for feeding worlLng steam to said low pressure cylinder for operating said low pressure cylinder during said exhaust steam diversion.

22. In a. multiple expansion engine-the combin nation of a low pressure steam working cylinder; a higher pressure steam working cylinder; means for feeding working steam tc said higher pressure cylinder; a passageway for feeding exhaust steam from said higher pressure cylinder to said low pressure cylinder; means disposed in said passageway for diverting said exhaust steam therefrom to prevent said exhaust steam from reaching said low pressure cylinder; means disposed in said passageway between said diverting means and said higher pressure cylinder comprising a valve adapted to eiect exhaust steam back pressure for said higher pressure cylinder during said exhaust steam diversion; manual control means for said diverting means and said back pressure eiecting. means operable to simultaneously effeet said exhaust steam diversion and said exhaus-t steami back pressure; andi means for feeding working steam to said low pressure cylinder for operating said low pressure cylinder during said exhaust steam diversion.

23. In a triple expansion engine embodying a hi'fh pressure cylinder, an intermediate pressure cylinder and a low pressure cylinder, the combination of means for delivering live steam simultaneously to all of said cylinders for single expansion operation for starting said engine; means for delivering steam exhausted from said high pressure cylinder to operate said intermediate pressure cylinder after said starting operation; means for delivering steam exhausted from said intermediate pressure cylinder to operate said low pressure cylinder during triple expansion operation of said engine; means for automatically cutting on delivery of live steam for said intermediate pressure cylinder when said high pressure cylinder exhaust steam is suicient for operation of said intermediate pressure cylinder; and means for automatically cutting off delivery of live steam for said low pressure cylinder when exaust steam delivered from said intermediate pressure cylinder is suicient for operating said low pressure cylinder.

24. In a triple expansion engine, the combination of a high pressure steam working cylinder; an intermediate pressure steam working cylinder; two low pressure steam working cylinders; means for delivering high pressure steam to said high pressure cylinder for operating said cylinder; means for delivering live steam at a reduced pressure below the pressure of said steam delivered to said high pressure cylinder, for operating said intermediate pressure cylinder; means for delivering live steam at a reduced pressure, below the pressure of said live steam delivered for said intermediate pressure cylinder, for operating said low pressure cylinders; means for delivering steam exhausted from said high pressureA cylinder for normal operation of said intermediate pressure cylinder; and means for delivering steam exhausted from said intermediate pressure cylinder for normal operation of said low pressure cylinders, whereby the steam delivered for operating said low pressure cylinders will be at a pressure reduced below the pressure of steam delivered to said intermediate pressure cylinder both during operation of said low pressure cylinders by exhaust steam and by live steam.

25. In a multiple expansion engine, the combination of a low pressure steam working cylinder; a higher pressure steam working cylinder; means for feeding working steam to said higher pressure cylinder; a normally substantially unrestricted passageway for feeding exhaust steam from said higher pressure cylinder to said low pressure cylinder; a second unrestricted passageway in communication with the atmosphere; means for' diverting. exhaust steam: from the first said passageway to said second passageway for unrestricted release therethrough to the atmosphere to prevent said exhaust steam from reaching said low pressure cylinder; means disposed inthe rst said passageway between said higher pressure cylinder and said diverting means for effecting exhaust steam back pressure for said higher pressure cylinder during said exhaust steam diversion; and means for feeding working 26. In a multiple expansion engine, the com- `binationof a low pressure steam working cylinder; a higher pressure steam working cylinder; means for feeding working steam to said higher `pressure cylinder; a normally substantially uni restricted passageway for feeding exhaust steam from said higher pressure cylinder to said low pressure cylinder; a second unrestricted passage- Way in communication with the atmosphere; means normally closing said second passageway, operable to open said second passageway to effect, by said opening, diversion of exhaust steam from the first said passageway to said second passageway for unrestricted release therethrough to the atmosphere to prevent said exhaust steam from reaching said low pressure cylinder; means disposed in the rst said passageway between said higher pressure cylinder and said diverting means n for eiecting exhaust steam back pressure for said higher pressure cylinder when said second passageway is open and saidexhaust steam is being released to the atmosphere; and means operable by said opening for feeding working steam to said low pressure cylinder during said exhaust steam diversion.

HARRY S. BURNHAM.` 

